#Safetypin was inspired by “I’ll ride with you,” an Australian campaign to support and protect Muslims from backlask in the wake of a terrorist attack. By wearing a safety pin, people are marking themselves out as allies in the fight against racism.

After several days of fear and uncertainty in the U.K., #safetypin’s virality feels like the direct result of a nationwide desire to “do something.” It caught on like wildfire, and people have already reported instances of it having an impact in real life. But for #safetypin to really make a difference, wearers must take its meaning to heart. That’s why, alongside the viral hashtag, two instruction manuals have become very popular over the past few days: A 2015 Guardian article about responding to racist attacks, and a guide to intervening against public harassment, from the organization United Against Racism.

Gavia Baker-Whitelaw is a staff writer at the Daily Dot, covering geek culture and fandom. Specializing in sci-fi movies and superheroes, she also appears as a film and TV critic on BBC radio. Elsewhere, she co-hosts the pop culture podcast Overinvested. Follow her on Twitter: @Hello_Tailor